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Toxicological information

Skin irritation / corrosion

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Administrative data

Endpoint:
skin irritation: in vivo
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: GLP guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2006
Report Date:
2006

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 404 (Acute Dermal Irritation / Corrosion)
Deviations:
no
GLP compliance:
yes (incl. certificate)

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): 1,5-Naphthylene diisocyanate
- Physical state: solid
- Purity: > 99.5 %
- Lot/batch No.: P3YE591000
- Storage condition of test material: room temperature

Test animals

Species:
rabbit
Strain:
New Zealand White
Details on test animals and environmental conditions:
TEST ANIMALS
- Sex: female
- Source: Charles River, Kißlegg, Germany
- Age at study initiation: adult
- Weight at study initiation: 2300-3600 g
- Housing: individual
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: at least 5 days


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 +/- 3
- Humidity (%): 50 +/- 25
- Photoperiod (hrs dark / hrs light): 12 / 12

Test system

Type of coverage:
semiocclusive
Preparation of test site:
shaved
Vehicle:
other: moistened with corn oil
Controls:
other: contralateral untreated skin area of test animals served as control
Amount / concentration applied:
Amount: 0.5 g
Duration of treatment / exposure:
4 hours
Observation period:
1, 24, 48, 72 hours, 7 and 14 days after patch removal
Number of animals:
3
Details on study design:
TEST SITE
- Area of exposure: approx. 2.5 x 2.5 cm
- Type of wrap if used: gauze patch

REMOVAL OF TEST SUBSTANCE
- Washing: treated skin area carefully washed with water
- Time after start of exposure: 4 hours

SCORING SYSTEM: according to DRAIZE

Results and discussion

In vivo

Resultsopen allclose all
Irritation parameter:
erythema score
Basis:
animal #1
Time point:
other: 24, 48, 72 hours
Score:
1 - 2
Max. score:
4
Reversibility:
fully reversible within: 14 days
Remarks on result:
other: mean score after 72 hours: 1.7
Irritation parameter:
edema score
Basis:
animal #1
Time point:
other: 24, 48, 72 hours
Score:
0
Max. score:
4
Reversibility:
other: not applicable
Remarks on result:
other: mean score after 72 hours: 0.0
Irritation parameter:
erythema score
Basis:
animal #2
Time point:
other: 24, 48, 72 hours
Score:
2 - 3
Max. score:
4
Reversibility:
fully reversible within: 14 days
Remarks on result:
other: mean score after 72 hours: 2.7
Irritation parameter:
edema score
Basis:
animal #2
Time point:
other: 24, 48, 72 hours
Score:
1 - 2
Max. score:
4
Reversibility:
fully reversible within: 7 days
Remarks on result:
other: mean score after 72 hours: 1.7
Irritation parameter:
erythema score
Basis:
animal #3
Time point:
other: 24, 48, 72 hours
Score:
1 - 2
Max. score:
4
Reversibility:
fully reversible within: 14 days
Remarks on result:
other: mean score after 72 hours: 1.7
Irritation parameter:
edema score
Basis:
animal #3
Time point:
other: 24, 48, 72 hours
Score:
0 - 1
Max. score:
4
Reversibility:
fully reversible within: 7 days
Remarks on result:
other: mean score after 72 hours: 0.7
Other effects:
No relevant systemic intolerance reactions were observed.

Any other information on results incl. tables

Irritant Effects on the Skin (Exposure: 4 hours):


Observation time               1h 24h 48h 72h day7 day14
Animal 1, 
Erythema (redness)
 and eschar formation           0   1   2   2   1    0
Oedema formation                0   0   0   0   0    0

Animal 2,
Erythema (redness)
 and eschar formation           0   2   3   3   1    0
Oedema formation                0   1   2   2   0    0

Animal 3,
Erythema (redness)
 and eschar formation           0   1   2   2   1    0
Oedema formation                0   0   1   1   0    0

Animal 1, day 7*: desquamation at the treated skin area
Animal 2, day 7*: desquamation at the treated skin area
* = after patch removal

Applicant's summary and conclusion

Conclusions:




Classification: not irritating
Executive summary:

In a dermal irritation/corrosion study according to OECD TG 404 1,5-Naphthylene diisocyanate (NDI) was applied under semiocclusive dressings for 4 hours to the shaved skin of 3 female rabbits. Skin irritation was assessed after 1, 24, 48, 72 hours and 7 and 14 days using the Draize scale. The mean irritation index for erythema was 2.0 of max. 4 (1.7 -2.7), the mean irritation index for edema was 0.8 of max. 4 (0.0 -1.7). Signs were fully reversible in all animals within two weeks. The weight of these evidences

indicates that the test substance may be considered as "slightly to moderately irritating to the skin". No relevant systemic intolerance reactions were observed.

According to classification criteria NDI is not an irritant to the skin.